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Thermochemical Equation Determine Mass

  1. Nov 25, 2011 #1
    So I am doing practice problems from the text book and it states:

    Given the thermochemical equation: 2Cu2O(s) → 4Cu(s) + O2, ΔH =+333.8 kJ/mol, calculate the mass of copper produced when 1.47 x 104 kJ is consumed in this reaction

    My attempt

    (1.47 x 104 kJ)/(33.8 kJ/mol )= 44 mol x 2 2 60=5.284 kg
    BUT This is wrong and I dont know why...the answer is 11.2 kg
  2. jcsd
  3. Nov 25, 2011 #2


    User Avatar

    Staff: Mentor

    No idea what you did, what is "2 2 60"?

    It is 333.8 kJ per "mole of reaction", not "mole of copper".
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